Various real time situations require a group call setup in a communication system to enable different users in different geographical locations having varying signal conditions to communicate at the same time. In certain situations, a group of users associated with the group call can be present within a particular geographic area or cellular sector and can be serviced using multicast or broadcast communication mode.
The present standards release 9 Long Term Evolution (LTE) system as described in http://www.3gpp.org/Release-9 provides broadcast services by selectively transmitting to cells within a preconfigured zone. However, the standards do not provide a method for selecting the actual transmitters for a multicast or broadcast communication. Also, the standards do not specify how to include or remove users to or from the multicast or broadcast communication based on a current spectral efficiency, RF signal conditions and mobility associated with the users.
Accordingly, there is a need for a method and apparatus for establishing and maintaining a spectrally efficient multicast group call.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.